Build modified streamline images

The official image from streamline does not currently work for the arm64
platform. As a temporary measure, the source code and docker build scripts
have been lifted from the official images and are used to build locally.

Some additional modifications are made to reduce overall image size, these
are documented in docker/README.md

docker/streamline-src/vendor/nesbot/carbon/sponsors.php

@@ -0,0 +1,129 @@
+<?php
+
+/**
+ * This file is part of the Carbon package.
+ *
+ * (c) Brian Nesbitt <brian@nesbot.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+use Carbon\CarbonImmutable;
+
+require_once __DIR__.'/vendor/autoload.php';
+
+function getMaxHistoryMonthsByAmount($amount): int
+{
+    if ($amount >= 50) {
+        return 6;
+    }
+
+    if ($amount >= 20) {
+        return 4;
+    }
+
+    return 2;
+}
+
+function getHtmlAttribute($rawValue): string
+{
+    return str_replace(
+        ['​', "\r"],
+        '',
+        trim(htmlspecialchars((string) $rawValue), "  \n\r\t\v\0"),
+    );
+}
+
+function getOpenCollectiveSponsors(): string
+{
+    $customSponsorImages = [
+        // For consistency and equity among sponsors, as of now, we kindly ask our sponsors
+        // to provide an image having a width/height ratio between 1/1 and 2/1.
+        // By default, we'll show the member picture from OpenCollective, and will resize it if bigger
+        // int(OpenCollective.MemberId) => ImageURL
+    ];
+
+    $members = json_decode(file_get_contents('https://opencollective.com/carbon/members/all.json'), true);
+
+    $list = array_filter($members, static function ($member): bool {
+        return ($member['lastTransactionAmount'] > 3 || $member['isActive']) &&
+            $member['role'] === 'BACKER' &&
+            $member['type'] !== 'USER' &&
+            (
+                $member['totalAmountDonated'] > 100 ||
+                $member['lastTransactionAt'] > CarbonImmutable::now()
+                    ->subMonthsNoOverflow(getMaxHistoryMonthsByAmount($member['lastTransactionAmount']))
+                    ->format('Y-m-d h:i') ||
+                $member['isActive'] && $member['lastTransactionAmount'] >= 30
+            );
+    });
+
+    $list = array_map(static function (array $member): array {
+        $createdAt = CarbonImmutable::parse($member['createdAt']);
+        $lastTransactionAt = CarbonImmutable::parse($member['lastTransactionAt']);
+
+        if ($createdAt->format('d H:i:s.u') > $lastTransactionAt->format('d H:i:s.u')) {
+            $createdAt = $createdAt
+                ->setDay($lastTransactionAt->day)
+                ->modify($lastTransactionAt->format('H:i:s.u'));
+        }
+
+        $monthlyContribution = (float) ($member['totalAmountDonated'] / ceil($createdAt->floatDiffInMonths()));
+
+        if (
+            $lastTransactionAt->isAfter('last month') &&
+            $member['lastTransactionAmount'] > $monthlyContribution
+        ) {
+            $monthlyContribution = (float) $member['lastTransactionAmount'];
+        }
+
+        $yearlyContribution = (float) ($member['totalAmountDonated'] / max(1, $createdAt->floatDiffInYears()));
+        $status = null;
+
+        if ($monthlyContribution > 29) {
+            $status = 'sponsor';
+        } elseif ($monthlyContribution > 4.5 || $yearlyContribution > 29) {
+            $status = 'backer';
+        } elseif ($member['totalAmountDonated'] > 0) {
+            $status = 'helper';
+        }
+
+        return array_merge($member, [
+            'star' => ($monthlyContribution > 98 || $yearlyContribution > 500),
+            'status' => $status,
+            'monthlyContribution' => $monthlyContribution,
+            'yearlyContribution' => $yearlyContribution,
+        ]);
+    }, $list);
+
+    usort($list, static function (array $a, array $b): int {
+        return ($b['monthlyContribution'] <=> $a['monthlyContribution'])
+            ?: ($b['totalAmountDonated'] <=> $a['totalAmountDonated']);
+    });
+
+    return implode('', array_map(static function (array $member) use ($customSponsorImages): string {
+        $href = htmlspecialchars($member['website'] ?? $member['profile']);
+        $src = $customSponsorImages[$member['MemberId'] ?? ''] ?? $member['image'] ?? (strtr($member['profile'], ['https://opencollective.com/' => 'https://images.opencollective.com/']).'/avatar/256.png');
+        [$x, $y] = @getimagesize($src) ?: [0, 0];
+        $validImage = ($x && $y);
+        $src = $validImage ? htmlspecialchars($src) : 'https://opencollective.com/static/images/default-guest-logo.svg';
+        $height = $member['status'] === 'sponsor' ? 64 : 42;
+        $width = min($height * 2, $validImage ? round($x * $height / $y) : $height);
+        $href .= (strpos($href, '?') === false ? '?' : '&amp;').'utm_source=opencollective&amp;utm_medium=github&amp;utm_campaign=Carbon';
+        $title = getHtmlAttribute(($member['description'] ?? null) ?: $member['name']);
+        $alt = getHtmlAttribute($member['name']);
+
+        return "\n".'<a title="'.$title.'" href="'.$href.'" target="_blank">'.
+            '<img alt="'.$alt.'" src="'.$src.'" width="'.$width.'" height="'.$height.'">'.
+            '</a>';
+    }, $list))."\n";
+}
+
+file_put_contents('readme.md', preg_replace_callback(
+    '/(<!-- <open-collective-sponsors> -->)[\s\S]+(<!-- <\/open-collective-sponsors> -->)/',
+    static function (array $match): string {
+        return $match[1].getOpenCollectiveSponsors().$match[2];
+    },
+    file_get_contents('readme.md')
+));